@patric.forsgard Could you please explain this in more detail. Currently we add the campaign code to OrderCarrier.CampaignInfo . What do we need to do in order to be able to apply multiple campaign codes on that property and get the expected result out of the campaign engine?
This article will describe how you can create an own campaign condition and this condition need to validate the value in the OrderCarrier.CampaignInfo to see if the action should be applied.
When the custom condition is created and added to the solution it should be possible to add that as a condition for the campaign action. Then the custom condition should be used instead of the default voucher code condition.